Shafilea’s badly-decomposed body was found nearly five months later beside a river in the Lake District.

Mr Edis said police carried out a lengthy investigation but failed to solve the mystery of her death.

However, in August 2010, Shafilea’s younger sister, Rukish, claimed she had been a witness to the killing. It was, said Mr Edis, the final piece in the puzzle.

Rukish, who has since changed her name to Alesha, originally made the allegation to friends shortly after her sister’s disappearance.

But she then retracted the claim and would not repeat it for another seven years.

She did so after being arrested for her part in a robbery at her parents’ home. Miss Ahmed, now 23, had been prosecuted over the crime and pleaded guilty.

Shafilea Ahmed, left and her parents Iftikhar andFarzana Ahmed

Mr Edis told the jury: “You will have to decide whether you can really believe what she said or not.

“If she is telling the truth, she has lived for the last nine years under the most extraordinary circumstances.

“If she is telling the truth this whole family, since September 2003, has been living in extraordinary circumstances.

“What an extraordinary thing to say of your parents, if it is true, that you were there and watching them murder your sister.”

Mr Edis described Shafilea as “a thoroughly westernised young British girl” who was reluctant to follow standards set by her parents.

“In particular she wanted to have boyfriends like most 16 and 17-year-old girls do, and that caused an intense pressure in the family.

“The prosecution say that her parents embarked upon a campaign of domestic violence and abuse designed to force her to conform so that she would behave in the way they expected.”

Shafilia had twice run away from home in the year before her disappearance.

On the second occasion she was “effectively recaptured – abducted” – by her father as she tried to return to school.

Once back at the family home she found herself in an environment of “silence and denial”.

A short time later she was taken to rural Pakistan, with her parents intending that she get married and remain there.

She told friends it was a forced marriage, and while at her grandparents’ home swallowed a quantity of bleach either as an act of self-harm or in a suicide attempt.

The “act of desperation” ended her parents’ plans for a wedding, but it also caused such serious damage to the teenager’s throat that she was admitted to Warrington General Hospital as soon as she returned to Britain.

Her parents had previously tried to exert control by taking her mobile phone, removing money from her bank account and forcing her to leave a part-time job.

Upon her return from Pakistan she began complaining that they were being violent towards her.

“The trouble she was describing that autumn was serious and causing her considerable distress,” said Mr Edis.

“As far as is known, no one else ever caused her any distress apart from her parents.”

On the two occasions Shafilea ran away from home there were phone calls, texts and bank transactions.

But when she disappeared in September 2003 there were none of these. “There was just silence,” said Mr Edis.